package net.jueb.sniff4j.extr.util;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;

/**
 * GZIP工具
 * 
 * @author <a href="mailto:zlex.dongliang@gmail.com">梁栋</a>
 * @since 1.0
 */
public abstract class GZipUtils {

	public static final int BUFFER = 1024;
	public static final String EXT = ".gz";

	/**
	 * 数据压缩
	 * 
	 * @param data
	 * @return
	 * @throws Exception
	 */
	public static byte[] compress(byte[] data)
	{
		byte[] out=new byte[0];
		try {
			ByteArrayInputStream bais = new ByteArrayInputStream(data);
			ByteArrayOutputStream baos = new ByteArrayOutputStream();
			// 压缩
			compress(bais, baos);
			out= baos.toByteArray();
			baos.flush();
			baos.close();
			bais.close();
		} catch (Exception e) {
			// TODO: handle exception
		}
		return out;
	}

	/**
	 * 文件压缩
	 * 
	 * @param file
	 * @throws Exception
	 */
	public static void compress(File file) throws Exception {
		compress(file, true);
	}

	/**
	 * 文件压缩
	 * 
	 * @param file
	 * @param delete
	 *            是否删除原始文件
	 * @throws Exception
	 */
	public static void compress(File file, boolean delete) throws Exception {
		FileInputStream fis = new FileInputStream(file);
		FileOutputStream fos = new FileOutputStream(file.getPath() + EXT);

		compress(fis, fos);

		fis.close();
		fos.flush();
		fos.close();

		if (delete) {
			file.delete();
		}
	}

	/**
	 * 数据压缩
	 * 
	 * @param is
	 * @param os
	 * @throws Exception
	 */
	public static void compress(InputStream is, OutputStream os)
			throws Exception {

		GZIPOutputStream gos = new GZIPOutputStream(os);

		int count;
		byte data[] = new byte[BUFFER];
		while ((count = is.read(data, 0, BUFFER)) != -1) {
			gos.write(data, 0, count);
		}

		gos.finish();

		gos.flush();
		gos.close();
	}

	/**
	 * 文件压缩
	 * 
	 * @param path
	 * @throws Exception
	 */
	public static void compress(String path) throws Exception {
		compress(path, true);
	}

	/**
	 * 文件压缩
	 * 
	 * @param path
	 * @param delete
	 *            是否删除原始文件
	 * @throws Exception
	 */
	public static void compress(String path, boolean delete) throws Exception {
		File file = new File(path);
		compress(file, delete);
	}

	/**
	 * 数据解压缩
	 * 
	 * @param data
	 * @return
	 * @throws Exception
	 */
	public static byte[] decompress(byte[] data) 
	{
		byte[] out=new byte[0];
		try {
			ByteArrayInputStream bais = new ByteArrayInputStream(data);
			ByteArrayOutputStream baos = new ByteArrayOutputStream();
			// 解压缩
			decompress(bais, baos);
			out = baos.toByteArray();
			baos.flush();
			baos.close();
			bais.close();
		} catch (Exception e) {
			// TODO: handle exception
		}
		return out;
	}

	/**
	 * 文件解压缩
	 * 
	 * @param file
	 * @throws Exception
	 */
	public static void decompress(File file) throws Exception {
		decompress(file, true);
	}

	/**
	 * 文件解压缩
	 * 
	 * @param file
	 * @param delete
	 *            是否删除原始文件
	 * @throws Exception
	 */
	public static void decompress(File file, boolean delete) throws Exception {
		FileInputStream fis = new FileInputStream(file);
		FileOutputStream fos = new FileOutputStream(file.getPath().replace(EXT,
				""));
		decompress(fis, fos);
		fis.close();
		fos.flush();
		fos.close();

		if (delete) {
			file.delete();
		}
	}

	/**
	 * 数据解压缩
	 * 
	 * @param is
	 * @param os
	 * @throws Exception
	 */
	public static void decompress(InputStream is, OutputStream os)
			throws Exception {

		GZIPInputStream gis = new GZIPInputStream(is);

		int count;
		byte data[] = new byte[BUFFER];
		while ((count = gis.read(data, 0, BUFFER)) != -1) {
			os.write(data, 0, count);
		}

		gis.close();
	}

	/**
	 * 文件解压缩
	 * 
	 * @param path
	 * @throws Exception
	 */
	public static void decompress(String path) throws Exception {
		decompress(path, true);
	}

	/**
	 * 文件解压缩
	 * 
	 * @param path
	 * @param delete
	 *            是否删除原始文件
	 * @throws Exception
	 */
	public static void decompress(String path, boolean delete) throws Exception {
		File file = new File(path);
		decompress(file, delete);
	}

}
